Definition: Triangles are three sided polygons, with angles adding up to 180 degrees.

Types of Triangles There are many different types of triangles including: equilateral, isosceles, scalene, right, obtuse, and acute.

Equilateral Triangle - An equilateral triangle is a triangle with three equal side lengths and three equal angles of 60 degrees.

Isosceles Triangle
An isosceles triangle has only two equal side lengths and two equal angles.

Scalene Triangle
A scalene triangle has no equal sides, and no equal angles.

Right Angle Triangle

A right angle triangle has one 90° internal angle.The side opposite to the right angle is the hypotenuse which it is the longest side in the right triangle. The other two sides are the legs of the triangle.

Obtuse Angle Triangle

A obtuse angle triangle has one internal angle that is greater than 90°. It is also an Oblique triangle ( no internal angle equal to 90° )

Acute Angle Triangle

An acute angle triangle has no angles greater then 90°. It is also and oblique triangle.

Perimeter & Area

To calculate perimeter of a triangle we use P=s+s+s.
Remember to always use units, and never put a ² or a ³ because those are for area and volume

P=s+s+s
=7+4+7
=18cm

To calculate the area of a triangle we use A=bh/2
Remember to include units, the ² behind your units, ie: cm², m², km², and to divide by 2 at the end!

A=bh/2
=(4)(6)/2
=24/2
=12cm²

Pythagorean Theorem

In math, we use Pythagorean theorem to find the missing side of a right angle triangle. For example:

Ok, so if we wanna find the missing side length, or "c", we use c²=a²+b²

( A and B can be any measurement that is there on the line, it doesn't matter the order, but C will always be the hypotenuse)

There is also a couple other ways in solving a triangles missing sides rather than using the Pythagorean theorem.

Sines: sin A = a/c, sin B = b/c.

Cosines: cos A = b/c, cos B = a/c.

Tangents: tan A = a/b, tan B = b/a.

Meaning of the word...

Sines: Ratio of the length of the side opposite the given angle to the length of the hypotenuse of a right-angled triangle

Cosines: Ratio of the adjacent side to the hypotenuse of a right-angled triangle

Tangents: Ratio of the opposite to the adjacent side of a right-angled triangle

Adjacent: Things are next to each other. (Beside)

Real World Application

There is many other uses for triangles besides just math, they are used in lots of modern day structures like housing, bridges, electric pylons, and artwork can also be used in flags and signs.

Marked June 7th

Triangles## Definition: Triangles are three sided polygons, with angles adding up to 180 degrees.

Types of TrianglesThere are many different types of triangles including: equilateral, isosceles, scalene, right, obtuse, and acute.Equilateral Triangle - An equilateral triangle is a triangle withthree equal side lengthsand three equal angles of60 degrees.Isosceles TriangleAn isosceles triangle has only

two equal side lengthsandtwo equal angles.Scalene TriangleA scalene triangle has

sides, andno equalangles.no equal## Right Angle Triangle

## A right angle triangle has one 90° internal angle.The side opposite to the right angle is the hypotenuse which it is the longest side in the right triangle. The other two sides are the

legs of the triangle.Obtuse Angle Triangle## A obtuse angle triangle has

oneinternal angle that is greater than 90°. It is also an Oblique triangle ( no internal angle equal to 90° )Acute Angle Triangle## An acute angle triangle has no angles greater then 90°. It is also and oblique triangle.

Perimeter & AreaTo calculate

perimeterof a triangle we use P=s+s+s.Remember to always use units, and never put a ² or a ³ because those are for area and volume

P=s+s+s

=7+4+7

=18cm

To calculate the

areaof a triangle we use A=bh/2Remember to include units, the ² behind your units, ie: cm², m², km², and to divide by 2 at the end!

A=bh/2

=(4)(6)/2

=24/2

=12cm²

Pythagorean TheoremIn math, we use Pythagorean theorem to find the missing side of a right angle triangle. For example:

Ok, so if we wanna find the missing side length, or "c", we use c²=a²+b²

## ( A and B can be any measurement that is there on the line, it doesn't matter the order, but C will always be the hypotenuse)

## So...

c²=a²+b²c²=4²+5²

c²=16+25

c²=41

/c²=/41

c=6.4 (rounded) -or- /41

There is also a couple other ways in solving a triangles missing sides rather than using the Pythagorean theorem.

A=a/c,sinB=b/c.A=b/c,cosB=a/c.A=a/b,tanB=b/a.## Meaning of the word...

## Sines: Ratio of the length of the side opposite the given angle to the length of the hypotenuse of a right-angled triangle

## Cosines: Ratio of the adjacent side to the hypotenuse of a right-angled triangle

## Tangents: Ratio of the opposite to the adjacent side of a right-angled triangle

## Adjacent: Things are next to each other. (Beside)

Real World ApplicationThere is many other uses for triangles besides just math, they are used in lots of modern day structures like housing, bridges, electric pylons, and artwork can also be used in flags and signs.

Citations:Triangles(2005). Retrieved December 10, 2008, from http://www.mathsisfun.com/triangle.htmlJoyce, D. E. (1999).

Right Angles. Retrieved December 18, 2008.## Pictures:

## scalene triangle - http://www.mathsisfun.com/triangle.html

## right angle triangle - http://www.mathopenref.com/images/triangle/hypotenuse.gif

## obtuse angle triangle - http://mathworld.wolfram.com/ObtuseTriangle.html

## acute angle triangle -

http://commons.wikimedia.org/wiki/File:Triangle-acute.svgroof truss picture - http://www.renovation-headquarters.com/images8/roof-truss-2.jpg## other triangle-http://www.emis.de/journals/EJC/Surveys/ds5/gifs/5-VD-triangles.gif

## Real World Application Pictures:

http://www.rogersconnection.com/triangles/images/bridge2.jpghttp://www.rogersconnection.com/triangles/images/bridge1.jpg

http://www.pinnacleluxurytours.com/images/france_itinerary1/04-Eiffel%20Tower.jpg

http://image34.webshots.com/34/3/72/87/2662372870081606937cfqRrb_fs.jpg

http://www.travelblog.org/World/flags/bahamian-large-flag-bf.gif

## http://www.istockphoto.com/file_thumbview_approve/2960168/2/istockphoto_2960168-triangle-sign-clear.jpg

## Created By:

## Brandon E

## Jared W

## Will H